THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

HEIDI COLLINS, CNN ANCHOR: We want to take you back to Matthew Chance now in Baghdad, where he's been monitoring that U.S. Black Hawk helicopter crash -- hello once again, Matthew. What's the very latest now?

MATTHEW CHANCE, CNN CORRESPONDENT: Heidi, details still very sketchy about what caused this incident and, indeed, how many people have been killed or injured. The latest figures that we have are that four U.S. personnel have been killed as a result of this Black Hawk helicopter crashing just north of the town of Tikrit in north central Iraq. Of course, Tikrit being Saddam Hussein's hometown.

It's not clear either at this stage whether the helicopter was brought down by hostile fire, by the insurgents who have been fighting against the U.S. and coalition presence in this country, or whether it was some kind of technical failure that led it to crash. Certainly it was traveling en route to Camp Iron Horse, which is the main U.S. military base inside of Tikrit, when, along with a second chopper, when it came down just a short distance from the outskirts of the camp perimeter.

The pilot of the second chopper said that he didn't see any hostile fire as a result, you know, which may have resulted in this incident, but obviously given the events of last Sunday, when 15 U.S. service people were killed when their Chinook helicopter was blasted from the skies by what eyewitnesses said was a surface to air missile, the possibility of it being hostile fire is a very definite one. It's being investigated at the moment.

U.S. helicopters rescue teams have moved to the scene to extract the casualties and to gather whatever forensic evidence they can -- Heidi.

COLLINS: It always takes a little bit of -- some time to figure out what happened, of course.

Matthew, we'll keep our eye on that story and check back with you should we learn any more.

I also want to ask you, before we let you go, about Mosul, learning that just a few hours after this first helicopter crash, another soldier died there.

CHANCE: Yes, I mean this is the kind of daily attack the U.S. and coalition forces are finding themselves coming under here in certain areas across Iraq, the latest one coming from the north central town of Mosul where, according to the spokesman of the 101st Airborne Division, one of their convoys came under attack just outside of Mosul from rocket propelled grenade fire and small arms fire. They're telling us that at least one U.S. soldier this morning was killed in that incident. Another six are said to be injured.

But both of these kinds of incidents underscoring just how hostile a place Iraq is for the U.S. and the coalition forces operating here.

COLLINS: All right, Matthew Chance live from Baghdad this morning.

Matthew, thanks so much.

TO ORDER A VIDEO OF THIS TRANSCRIPT, PLEASE CALL 800-CNN-NEWS OR USE OUR SECURE ONLINE ORDER FORM LOCATED AT www.fdch.com